Imagine that you have some servers running applications and you need to find a way to backup the files and preserve their properties, like the user, group, date, and permissions. How do you do that?

Does exist many ways to create a backup solution, but here I’ll focus on a backup solution to:

  • Copy all files from one Linux server to another Linux.
  • Preserve all files properties, including date change and file permissions.
  • Allow a file restore simply by rsync the content back to the original server.

This is not a solution for any kind of backup routine!

Requirements

  • rsync
  • ssh authorized keys configured

You will need to install the rsync package. For example:

# Ubuntu/Debian
apt update
apt install -y rsync

# CentOS/Fedora
dnf install -y rsync
You also need to share the origin server public as an authorized key on the destiny server, so will not be required to enter the password on any `rsync` command execution. You can check how to do that on this post:
Luiz Felipe F M CostaLuiz Felipe F M Costa
Setup SSH login to don’t ask password again
If you use the SSH a lot of time or want to sync files, probably you need to type your password many times a day. The way to avoid this problem and create a free communication between two Linux computers is to share the public ssh key. If you want

The rsync archive command

The command that you’ll need is this:

# rsync that preservers all files attributes
rsync -zavh --delete root@origin.thenets.org:/mnt/storage /mnt/backup
Now, explaining the command:

  • The user:
    You will need to run the command as root to be able to preserve the uid attribute.

  • Command arguments

    • -z compress file data during the transfer
    • -a archive mode; equals -rlptgoD
      (the most important arg. That one will preserve all files attributes)
    • -v increase verbosity (list all files been transferred)
    • -h output numbers in a human-readable format
    • --delete delete extraneous files from destination dirs
      (if a file was deleted on the source, so will also delete on destination)

Reference